Eroding out of the dune face along the shoreline of a small bay is a midden, the term archaeologists use for a deposit of domestic waste, in this case composed overwhelmingly of limpet shells. These accumulations are rarely glamorous, but they are among the most informative things a coastal community can leave behind, capturing in compressed layers exactly what people were gathering, cooking, and discarding over generations.

The deposit at Gooreenatinny is extensive by any measure. One exposed section runs to around 88 metres in length, with clearly visible banded layers suggesting repeated, structured use of the same location over time. Rock armour, placed on the beach to slow coastal erosion, now runs across what may be the middle portion of the site, and a further section of approximately 23 metres has been identified to the north-east of it. If the two sections are indeed continuous, the midden would stretch to something in the region of 167 metres in total. Radiocarbon dating of samples taken in 1988 returned a calibrated date of AD 1000 to 1150, placing the deposit firmly in the early medieval period, when island communities along this coastline were harvesting shellfish as a significant part of their diet. An earlier survey in 1983 had also noted burnt stone, hearths, and charcoal at the site, though these features were not visible during a revisit in 2014, suggesting that erosion and shifting sand continue to alter what is exposed at any given time.

The dunes here vary considerably in height, from around one metre to nearly four, and the midden material emerges from the dune face rather than lying on the surface, so it rewards careful observation. The site sits at the south-west corner of Omey, an island accessible on foot across the strand at low tide from near Claddaghduff. The visibility of the midden layers will depend on recent weather and the current state of the dunes, conditions that have been changing the site steadily for decades.